Derivative And Credit-Related Financial Instruments (Schedule Of Derivative Instruments) (Details) - USD ($) $ in Millions		Jun. 30, 2024		Dec. 31, 2023
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	$ 72,768		$ 70,737
Fair Value of Gross Derivative Assets		800		1,019
Fair Value of Gross Derivative Liabilities		1,060		1,206
Derivative asset, Netting adjustment - Offsetting derivative assets		(283)		(311)
Derivative liabilities, Netting adjustment - Offsetting derivative assets		(283)		(311)
Derivative assets, Netting adjustment - Cash collateral received		(85)		(143)
Derivative liabilities, Netting adjustment, Cash collateral posted		(3)		(13)
Net derivative assets included in the Consolidated Balance Sheets	[2]	432		565
Net derivative liabilities included in the Consolidated Balance Sheets	[2]	774		882
Derivative asset, securities pledged as collateral		(287)		(501)
Derivative liability, securities pledged as collateral		(78)		(4)
Net derivative assets after deducting amounts not offset in the Consolidated Balance Sheets		145		64
Net derivative liabilities after deducting amounts not offset in the Consolidated Balance Sheets		696		878
Credit valuation adjustments for counterparty credit risk		2
Risk management purposes
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	32,087		31,710
Fair Value of Gross Derivative Assets		1		1
Fair Value of Gross Derivative Liabilities		48		11
Risk management purposes | Derivatives designated as hedging instruments | Fair value swaps - receive fixed/pay floating | Swaps
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	7,300		6,300
Fair Value of Gross Derivative Assets		0		0
Fair Value of Gross Derivative Liabilities		3		0
Risk management purposes | Derivatives designated as hedging instruments | Cash flow swaps - receive fixed/pay floating | Swaps
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	24,150		24,850
Fair Value of Gross Derivative Assets		0		0
Fair Value of Gross Derivative Liabilities		45		8
Risk management purposes | Derivatives designated as hedging instruments | Cash flow swaps - receive fixed/pay floating | Forward Starting Swap
Derivatives, Fair Value [Line Items]
Notional/Contract Amount		750	[3]	2,000
Risk management purposes | Derivatives used as economic hedges | Spot, forwards and swaps
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	637		560
Fair Value of Gross Derivative Assets		1		1
Fair Value of Gross Derivative Liabilities		0		3
Customer-initiated and other activities
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	40,681		39,027
Fair Value of Gross Derivative Assets		799		1,018
Fair Value of Gross Derivative Liabilities		1,012		1,195
Customer-initiated and other activities | Interest rate contracts
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	22,109		22,470
Fair Value of Gross Derivative Assets		203		225
Fair Value of Gross Derivative Liabilities		432		427
Customer-initiated and other activities | Caps and floors written
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	1,607		1,577
Fair Value of Gross Derivative Assets		0		0
Fair Value of Gross Derivative Liabilities		14		18
Customer-initiated and other activities | Caps and floors purchased
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	1,607		1,577
Fair Value of Gross Derivative Assets		14		18
Fair Value of Gross Derivative Liabilities		0		0
Customer-initiated and other activities | Swaps
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	18,895		19,316
Fair Value of Gross Derivative Assets		189		207
Fair Value of Gross Derivative Liabilities		418		409
Customer-initiated and other activities | Energy contracts
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	15,624		13,806
Fair Value of Gross Derivative Assets		565		758
Fair Value of Gross Derivative Liabilities		558		736
Customer-initiated and other activities | Caps and floors written
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	4,161		3,719
Fair Value of Gross Derivative Assets		2		3
Fair Value of Gross Derivative Liabilities		243		291
Customer-initiated and other activities | Caps and floors purchased
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	4,161		3,719
Fair Value of Gross Derivative Assets		229		292
Fair Value of Gross Derivative Liabilities		2		3
Customer-initiated and other activities | Swaps
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	7,302		6,368
Fair Value of Gross Derivative Assets		334		463
Fair Value of Gross Derivative Liabilities		313		442
Customer-initiated and other activities | Spot, forwards, options and swaps
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	2,948		2,751
Fair Value of Gross Derivative Assets		31		35
Fair Value of Gross Derivative Liabilities		$ 22		$ 32

[1] Notional or contractual amounts, which represent the extent of involvement in the derivatives market, are used to determine the contractual cash flows required in accordance with the terms of the agreement. These amounts are typically not exchanged, significantly exceed amounts subject to credit or market risk and are not reflected in the Consolidated Balance Sheets.

[2] Net derivative assets are included in accrued income and other assets and net derivative liabilities are included in accrued expenses and other liabilities on the Consolidated Balance Sheets. Included in the fair value of net derivative assets and net derivative liabilities are credit valuation adjustments reflecting counterparty credit risk and credit risk of the Corporation. The fair value of net derivative assets included credit valuation adjustments for counterparty credit risk of $2 million and $3 million at June 30, 2024 and December 31, 2023, respectively.

[3] June 30, 2024 included $750 million of forward starting swaps that will become effective on their contractual start dates in 2024.